DUBLIN NATU&AL HISTORY SOaETT. 9 



After some further discussion, Db. J. R. Khtahan read a paper — 



OK XANTHO KIYULOSA AND OXnER DECAP0D0U8 CBU8TACBA OCCUBRINO AT 

 VAX.ENTIA ISLAND, CO. XEBBY. 



In recording this, the second notice of the occurrence of Xantho rivulosa 

 on the Irish shores, I metm to take the same opportunity to submit to 

 your Society such notes with regard to some of the more remarkable 

 Crustacea which occur at Valentia Island, as a hurried visit to that loca- 

 lity last summer, under unfavourable circumstances, aflforded me, com- 

 bining with them remarks on the distribution of the species around 

 Ireland generally, as far as the scanty materials at my command will 

 enable me to do. These, though imperfect, I am led to lay before 

 you, chiefly by the great lack of information on this subject which I 

 find pervades all our Natural Histories, even those very lately published. 



It is a matter much to be deplored, that naturalists generally do not 

 oftener avail themselves of opportunities of compiling comparative tables 

 of the productions of the various districts they may examine ; but, in- 

 stead thereof, sinking the naturalist in the mere collector, rush rather 

 after a multitude of specimens or species than a limited number of gene- 

 ral facts. I do not wish to undervalue the collector's labours, but rather 

 to prompt every collector to become a naturalist also, and by carefully 

 noting the special peculiarities of each district which he examines, to 

 enable himself and others thereby to arrive not only at particular con- 

 clusions as regards that locality, but also at general ones as regards the 

 Fauna of the entire country, and its bearings on the Fauna of the whole 

 world. That the importance of this matter is not overrated must be 

 apparent to any one who takes the trouble to examine even the best 

 arranged books of modem days, with regard to the distribution of our 

 marine animals, and (with, perhaps, the exception of the Molluscs) the 

 deficiency of authentic information wiU be apparent on even a super- 

 ficial examination, this deficiency in a great measure arising firam 

 observers having sought and noted the rarest, or what they considered 

 the rarest species, only. 



The principal data on which the following remarks as to distribu- 

 tion are founded are as follow : — For the north of Ireland generally, the 

 specimens in what is commonly known as the Ordnance Survey collec- 

 tion, or Down Survey collection, — a collection made by the officers of 

 the Ordnance Survey of Ireland, under the direction of Captain, now 

 Colonel Portlock, during the years 1839, &c., in the counties of Done- 

 gal, Antrim, Down, and Londonderry, and which is at present in the 

 Museum of Irish Industry. "Where this is referred to, the letters 0. C. 

 are placed after the locality. 



For the east coast, my own experience of Dublin Bay, assisted, in a 

 very few instances, by the collections of Dr. Ball and other kind friends. 



For the south, my own experience in Youghal and Ardmore, and 

 also J. V. Thompson's collection of Crustacea, now in the lloyal Dublin 

 Society's Museum; and also the Catalogue prepared by the Cork Cu- 



